Tus·ca·ny (tŭs'kə-nē') A region of northwest Italy between the northern Apennines and the Ligurian and Tyrrhenian seas. Inhabited in ancient times by the Etruscans, it fell to Rome in the mid-fourth century B.C. Tuscany was a grand duchy under the Medicis (1569-1860) and subsequently became united with the kingdom of Sardinia.